H. Hakan Oruckaptan

Pituitary adenomas: results of 684 surgically treated patients and review of the literature

BACKGROUND The outcome of patients with pituitary adenomas who were treated surgically with or without postoperative radiotherapy was analyzed. The purpose of this study was to determine the factors that strongly influence (A) tumor control, (B) the efficacy of surgery, and (C) radiotherapy based on the hormonal activity of adenomas and its invasion characteristics. METHODS Between 1982-1996, 684 patients with the diagnosis of pituitary adenoma were operated on. The mean age was 38 years and the mean follow-up time was 40.5 months. A total of 516 patients who were followed for more than 1 year were studied to analyze the effect of treatment modalities and invasion characteristics on tumor control. There were 297 patients with prolactinomas, 118 patients with somatotropinomas, 45 with corticotropinomas, 17 with mixed adenomas, two with thyrotropinomas, and 205 with null cell adenomas. All patients were classified according to Hardys modified radiological classification scheme and analyzed in invasive and noninvasive groups individually based on this classification system. In the early postoperative period, 230 of these patients were given conventional radiotherapy with a mean dose of 4400 cGy. The following factors were analyzed for prognostic significance in tumor control: the effects of surgery and radiotherapy based on tumor types and invasion characteristics, the existence of histologically proven invasion of the dura mater overlying the sellar floor, and the early results of topical bromocriptine application in macroprolactinoma patients. RESULTS Overall surgical complications and mortality rate were similar to those of large series reported in the literature. Except for the invasive somatotropinomas and null cell adenomas, statistical analysis demonstrated the ineffectiveness of radiotherapy on tumor control. We did not detect any positive correlation between the recurrence rate and mean recurrence time or dural invasion of the sellar floor. Topical bromocriptine application seemed to improve tumor control in 21 selected macroprolactinoma patients. CONCLUSION Conventional radiotherapy is not as effective as expected, considering its adverse effects. The increased side effects of radiotherapy in cases with supra-parasellar extension, especially to the optic pathway and hypothalamus, limit its benefits, which could be demonstrated only in invasive somatotropinomas and null cell adenomas. In contrast with our current beliefs, tumoral infiltration of the sellar dura mater is not a prognostic factor for recurrence and therefore should not be a criterion for radiotherapy after surgery. Topical application of bromocriptine into the sellar cavity after tumor removal seems to provide superior results compared with the conventional treatment modalities.

Neurocutaneous Melanosis Associated with Dandy-Walker Malformation

Neurocutaneous melanosis is a rare dysmorphogenesis associated with single or multiple giant pigmented cutaneous nevi and diffuse involvement of the leptomeninges anywhere in the central nervous system (CNS). It is interesting that almost 8–10% of patients had associated Dandy-Walker malformation in the literature, suggesting a common origin of the developmental abnormalities. In this article, we present a 2-year-old patient with neurocutaneous melanosis associated with Dandy-Walker malformation. We reviewed the literature and discuss the pathogenesis based on the preferred hypotheses so far.

Parafalcine chondrosarcoma: an unusual localization for a classical variant: Case report and review of the literature

BACKGROUND Intracranial chondroid tumors are infrequently seen in neurosurgical practice. These tumors usually arise from cartilaginous synchondroses at the base of the skull, but occasionally from the pluripotential mesenchymal cells of the meninges. We present here a case of classic low-grade giant chondrosarcoma of the falx cerebri. This is only the second case of this variant reported in this location, and we summarize the diagnostic criteria with a brief review of literature. CASE REPORT A 56-year-old female patient was admitted to the hospital with a history of progressive right-sided weakness occurring in the last 8 months and a recent grand mal seizure. Radiological evaluation demonstrated a large extra-axial mass in the left parafalcine area, suggesting a possible meningioma. An anterior interhemispheric approach enabled gross total removal of the tumor and a histologic diagnosis of a low-grade classic chondrosarcoma was made. The patient is currently stable and has shown no evidence of recurrence in more than 3 years without any adjuvant treatment. CONCLUSIONS Intracranial cartilaginous tumors include classical, mesenchymal and myxoid chondrosarcomas in addition to benign chondromas. Parafalcine localization should be considered for all these variants as well as for meningiomas, hemangiopericytomas, solitary fibrous tumors, and meningeal metastatic carcinomas. Detailed radiological evaluation, light microscopic and ultrastructural analyses, and immunocytochemistry are essential for correct diagnosis. In contrast to mesenchymal and myxoid types, the prognosis of classic variants is usually good and does not require adjuvant treatment modalities if a radical resection of the tumor can be obtained. Increased documentation of clinical, radiological, and histologic findings as well as response to treatment modalities will provide a better understanding of the pathophysiology of these rare tumors, and highlight the optimum treatment strategies

Benign Melanocytic Tumor in Infancy: Discussion on a Rare Case and Review of the Literature

Meningeal melanocytoma is an infrequent neoplasm of the central nervous system (CNS), especially in childhood and infancy. It was first described as an entity different from pigmented meningiomas and schwannomas in 1972, and few cases have been published so far. In this article, a 5-month-old male patient with meningeal melanocytoma is presented. This midline lesion was localized in the posterior fossa and manifested by hydrocephalus. The entire dural origin and extradural growing pattern in addition to the destruction of the adjacent occipital bone were the unexpected presentations since these tumors usually tend to locate on leptomeninges and to extend into the adjacent neural compartment rather than the outside. On the other hand, this case is the only one which had identical lesions in both surrenal glands and the left renal capsule, the structures containing neural-crest-derived cells outside the CNS. The prognostic criteria, differential diagnosis and its embryological aspects are discussed with an extensive review of the related existing literature.

Prolonged cerebral salt wasting syndrome associated with the intraventricular dissemination of brain tumors. Report of two cases and review of the literature

Hyponatremia is a frequent event in neurosurgery practice and is usually associated with subarachnoid hemorrhage, head trauma, infections and neoplasms. The two common clinical manifestations are the inappropriate secretion of antidiuretic hormone (SIADH) and the cerebral salt wasting syndrome (CSWS), which were usually attributed to each other due to identical clinical presentation. In contrast to the better-recognized SIADH, there has not been a uniform consensus over the humoral and neural mechanisms of CSWS and functional aspects of renal response. In this article, we report on 2 cases of a primitive neuroectodermal tumor with prolonged CSWS manifested during the intraventricular dissemination of primary disease and the high catabolic stage.

Combined Posterior and Posterolateral One-Stage Removal of a Giant Cervical Dumbbell Schwannoma

Objective: Huge dumbbell schwannomas in the cervical region are not a rare clinical entity in neurosurgical practice. Despite the benign nature, the adhesions between tumor capsule and spinal cord, vertebral artery, cervical plexus, and carotid sheath can complicate surgery, leading to a fatal outcome. We performed one-stage combined surgery through the posterior midline and an unusual posterolateral cervical route in the same position and describe its advantages. Method: We removed the intraspinal component totally through a posterior midline approach and freed spinal cord and vertebral artery. After removal of the posterolateral extraspinal component using the same incision, a posterolateral cervical approach along the posterior margin of sternocleidomastoid muscle was performed, and the anterolateral extraspinal tumor was excised totally through the dissection plane between anterior and middle scalene muscles. Results and Conclusions: The operative time was less than 3 h, and the patient was discharged on the 3rd postoperative day without any neurological sequel. The combination of posterior midline and posterolateral approach in large dumbbell schwannomas is easier to perform and a more safe technique than the combination with anterolateral accesses in the cervical region and also less invasive than the transuncodiscal technique in selected cases. This approach reduces the risk of neurovascular injury, since it does not require retraction and repositioning of the patient and, therefore, facilitates total excision and reduces the operative time.

Systemic administration of interleukin-10 attenuates early ischemic response following spinal cord ischemia reperfusion injury in rats.

BACKGROUND The aim of this experimental study was to investigate the early effects of interleukin-10 (IL-10) and interleukin-1beta antagonist (anti-IL-1beta) against cellular damage, inflammatory reactivity, lipid peroxidation (LPO), and myeloperoxidase (MPO) activity induced by spinal cord ischemia reperfusion injury (IRI). METHODS Thirty-two single strain female Albino rats were divided into four groups: control (sham-operated), IRI-alone, IL-10-treated (100 mug/kg), and anti-IL-1beta-treated (1 mg/kg) groups after IRI. IRI was induced by balloon occlusion of the aorta and simultaneous hypovolemia during occlusion. The animals were sacrificed at 24 h. Histopathological and ultrastructural analyses, biochemical studies for determination of LPO and MPO activity and Comet assays (single cell electrophoresis for detecting DNA single strand breaks) were performed in all study groups. RESULTS Compared with the levels of control (sham-operated) animals, IRI produced a significant increase in the levels of LPO and MPO activity, and prominent tissue damage characterized by leukocyte infiltration, edema and neuronal and glial damage in the affected spinal cord in 24 h. The administration of IL-10 decreased LPO and MPO activity, and suppressed initial inflammatory response in the first 24 h. The effects of anti-IL-1beta were limited to decrease in LPO activity without considerable evidence of cellular preservation. CONCLUSIONS These data suggest that systemic administration of IL-10 attenuates the early ischemic response, and may restrict the tissue damage in the first 24 h after spinal cord ischemia reperfusion injury. Anti-IL-1beta has no considerable effect in this time window. The results of this preliminary study promote further studies with longer time windows on the effects of anti-inflammatory cytokines in spinal cord IRI.

Isolated sphenoid sinus abscess: clinical and radiological failure in preoperative diagnosis. Case report and review of the literature.

BACKGROUND Isolated sphenoid sinusitis and abscess formation is a rare entity, which can lead to misdiagnosed or improperly treated patients and an unfavorable outcome. Invasion of the skull base and cavernous sinus usually causes cranial nerve palsies, suggesting a neoplasm at the initial presentation. CASE DESCRIPTION A case of isolated abscess in the sphenoid sinus is reported. The complete destruction of the clivus and its unexceptional radiological data, in addition to the absence of clinical and laboratory evidence of infection, led us to misdiagnose a possible clival chordoma during preoperative evaluation. The patient underwent an endonasal-transsphenoidal procedure for diagnosis and surgical removal. Surgical drainage and prolonged antimicrobial treatment resulted in complete clinical recovery. CONCLUSION Its close proximity to vital structures and slender bony structures may allow the infection to disseminate, with serious neurological complications. On the other hand, the variable clinical presentations and radiological data usually cause delayed or missed diagnosis in these cases. This emphasizes the importance of documentation of this unusual entity and its radiological manifestations.

No apparent role for neutrophils and neutrophil-derived myeloperoxidase in experimental subarachnoid haemorrhage and vasospasm: a preliminary study.

Summary¶Objective. The literature contains investigations and discussion of the role of neutrophils and neutrophil-derived myeloperoxidase (MPO) in inflammatory processes, local ischaemia, and ischaemia-reperfusion injury models. Our aim was to determine whether the same roles existed for neutrophils and the system involving neutrophil-derived MPO in experimental subarachnoid haemorrhage (SAH) and associated ischaemia. Material and Method. Forty-eight adult New Zealand white rabbits were divided into six groups of eight. The first SAH model was applied to 16 animals. Eight of these rabbits were sacrificed after 48 hours (Group 1) and the remaining eight were killed after 96 hours (Group 2). The second SAH model applied to another 16 rabbits, which were sacrificed in two groups at the above time periods, forming Groups 3 and 4, respectively. There were two groups of 8 control animals, one group per SAH model, and these rabbits were sacrificed after 48 hours. We carried out histopathological studies using haematoxylin and eosin (H&E) stain, elastin stain, MPO immunohistochemistry, and determination of basilar artery cross-sectional diameter. We also did biochemical analysis of cerebral hemisphere and brainstem specimens, measuring tissue lipid peroxidase and MPO activity. Results were compared between the groups and with their related controls. Results. In contrast to previous experimental findings in local ischaemia and ischaemia-reperfusion models, we found no histopathological or biochemical evidence to suggest a role for neutrophils and neutrophil-derived MPO in relation to subarachnoid haemorrhage and resultant vasospasm. Although we confirmed the successful induction of significant vasospasm and observed the clinical evidences of subsequent ischaemia, there was no notable accumulation of neutrophils or activity of neutrophil-derived MPO in the tissues studied. This suggests that the biological process induced by SAH follows a different pattern from that seen in local ischaemia and ischaemia-reperfusion injury.

Giant extracranial internal carotid artery aneurysm: A rare presentation with an oropharyngeal mass.

Aneurysms of the extracranial carotid arteries are infrequent lesions in both neurosurgery and cardiovascular surgery practice. Although the exact frequency is unclear, it has been reported in 1 of 60 to 1 of 800 of all aneurysms found at the other anatomic locations and in less than 1% of surgical procedures performed for carotid artery diseases. 1 Most of these aneurysms are believed to be the result of either traumatic or spontaneous dissections. Along with showing the outcome of these lesions, clinical and angiographic presentations show significant variations according to the etiology. 2,3 Traumatic aneurysms usually tend to manifest at the time of insult, or a few months after the insult, but occasionally show a prolonged history, whereas spontaneous lesions usually remain silent for years. Spontaneous dissections frequently affect the proximal segment of the internal carotid artery (ICA) and the bifurcation of the common carotid artery (CCA). 2 Bilateral involvement of the carotid system is not an infrequent event and suggests an underlying atherosclerotic disease, fibromuscular dysplasia, or other connective tissue disorders. The clinical manifestation of these lesions may vary from the serious ischemic deficits and lower cranial nerve palsies to an asymptomatic mass in the neck or a prolonged history of headache.